<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <!-- 缺失的第一个正数 -->
    <script>
      var firstMissingPositive = function (nums) {
        nums.sort((a, b) => a - b)
        let num = 1
        for (let i = 0; i < nums.length; i++) {
          if (nums[i] === num) {
            num++
          }
        }
        return num
      }
      // console.log(firstMissingPositive([1, 2, 0]))
      // console.log(firstMissingPositive([3, 4, -1, 1]))
      console.log(firstMissingPositive([7, 8, 9, 11, 12]))
    </script>
  </body>
</html>
